As a Black woman, he never seemed intimidating to me. It demonstrated his uncomfortableness with living in the diaspora. Yes, he blasted his song but never raised a hand to hurt anyone. To him, fighting the power and spreading his song was more important than any other message.
Of course, the Italians in the restaraunt felt challenged and afraid but only due to their racist beliefs. Having only Black customers but condemning his culture seemed a bit too much. It is one thing to ask for the music to be turned down. It's a different situation to tell someone to shut it off. Also, the hostility that Sal showed when asking made it hard to believe he had any attention to de-escalate.
When he was killed, in the end, it was due to the racial strife that made the pot boil over on that hot summer, Bed-stuy neighborhood. The police killed him because they never recognized his true humanity.